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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
K. Toi, M. Isobe, M. Osakabe, F. Watanabe, K. Ogawa, S. Yamamoto, N. Nakajima, D. A. Spong, K. Ida, T. Ido, T. Ito, S. Morita, K. Nagaoka, K. Narihara, M. Nishiura, S. Ohdachi, S. Sakakibara, A. Shimizu, K. Tanaka, Y. Todo, T. Tokuzawa, A. Weller, LHD Experiment Group
Fusion Science and Technology | Volume 58 | Number 1 | July-August 2010 | Pages 186-193
Chapter 4. MHD | Special Issue on Large Helical Device (LHD) | doi.org/10.13182/FST10-A10805
Articles are hosted by Taylor and Francis Online.
Energetic ion-driven magnetohydrodynamic instabilities such as Alfvén eigenmodes (AEs), energetic particle modes (EPMs), and their impacts on energetic ion confinement are being studied on the Large Helical Device (LHD). The magnetic configuration of this device is three dimensional and has negative magnetic shear over a whole radial region in the low-beta regime. Two types of toroidicity-induced Alfvén eigenmodes (TAEs) are typically observed in LHD plasmas that are heated by tangential neutral beam injection: One is localized in the plasma core region near a central TAE gap and the other is a global TAE having a radially extended eigenfunction. Core-localized TAEs with even and odd radial mode parities are often observed. The global TAE is usually observed in medium- to high-beta plasmas where broad regions with low magnetic shear are present. Helicity-induced Alfvén eigenmodes (HAEs), which exist in gaps unique to three-dimensional plasmas that have both toroidal and poloidal mode couplings, were detected for the first time. Recently, reversed magnetic shear Alfvén eigenmodes (RSAEs) having characteristic frequency sweeping were discovered in reversed magnetic shear (RS) plasmas produced by intense counter-neutral beam current drive. In the RS plasma, the geodesic acoustic mode (GAM) excited by energetic ions, which is a global-type mode different from localized GAM excited by drift waves, was also detected for the first time in a helical plasma. Nonlinear couplings between RSAE and GAM modes and also between two TAEs were observed. Bursts of TAEs and EPMs often enhance radial transport and loss of energetic ions at low toroidal magnetic field (<0.75 T).